JP4626275B2 - Automatic centrifuge - Google Patents

Description

The present invention is a useful substance i.e. a sample such as blood, cells or nucleic were centrifuged in fields such as medicine, Agriculture and pharmaceutical-physical relates positioning of the rotor of the automatic centrifugal device for loading and unloading the sample automatically .

  A conventional automatic centrifuge will be described with reference to FIG.

Automatic centrifugal device 1, the rotor 2 centrifuged accommodating a sample, a drive unit 3 for driving the rotor 2, to position the conveying means 4, the center and the height of the rotor 2 during loading and unloading to loading and unloading the sample It consists of a shaft support mechanism 5 and the like, and automatically performs the steps of sample loading, centrifugal separation and unloading.
As is well known, the rotor 2 is provided with four bucket suspension points. A rack (not shown) holding a plurality of test tubes (not shown) containing a sample is attached to the bucket, and the rotor 2 rotates at high speed. As a result, the sample in the test tube is centrifuged. The loading and unloading of the sample is performed in units of racks by the transporting means 4, and the rotor 2 is rotated 90 ° from the initial loading / unloading position so that the next bucket is positioned at the loading / unloading position by the transporting means 4. Thus, the rack can be carried in and out.

  The drive unit 3 is supported by a plurality of dampers 7 fixed to the frame 6, and a rotary shaft 8 having a spherical tip is supported by two ball bearings 9 a and 9 b at the center thereof. Yes. A servo motor 10 is connected to the lower end of the rotating shaft 8 by a coupling 11, and the upper rotor 2 is rotationally driven through the rotating shaft 8. The servo motor 10 is controlled by an operation control unit (not shown) so that the acceleration, deceleration, and rotation speed of the rotor 2 can be set.

  A head 12 that can be moved up and down is attached to the lower part of the shaft support mechanism 5, and the head 12 has a tapered shape. Further, the shaft support mechanism 5 is attached to a position above the rotation shaft 8 and coincident with the rotation center of the rotor 2.

  Next, the operation of the conventional automatic centrifuge 1 and the positioning of the rotor 2 will be described.

In order to load and unload the sample, the rotor 2 needs to be accurately stopped at the position of the transfer means 4. However, as described above, the drive unit 3 that drives the rotor 2 is supported by a damper 7 such as soft rubber or a spring for vibration isolation, so that the rotor 2 is easily shaken when stopped. For this reason, in the conventional automatic centrifugal apparatus 1, as described in Patent Document 1, centering of the rotating shaft 8 by the shaft support mechanism 5, that is , positioning in the rotational direction of the rotor 2 and positioning of the height of the rotor 2 are performed. Had gone. A specific operation example is shown below.

When the sample is loaded, first, the head 12 of the shaft support mechanism 5 moves downward to press the tip of the rotating shaft 8. At this time, the spherical surface at the tip of the rotating shaft 8 is guided by the taper of the head 12, and the rotating shaft 8 is centered, that is, the rotor 2 is positioned in the rotational direction . Further, the height of the rotor 2 is positioned by the pressing force of the head 12. Next, the rotor 2 is rotationally moved to the loading position by the servo motor 10, and although not shown in detail, the sample is sequentially carried into the bucket of the rotor 2 by the conveying means 4.
After carrying in, the rotor 2 is rotated about 90 °, and then the rotational direction and height of the rotor 2 are positioned again, and the sample is carried into the next bucket. By positioning and loading the rotor 2 four times, the sample loading into the four buckets is completed.

During centrifugation operation, the head 12 of the shaft supporting mechanism 5 is raised initially, to free the rotation axis 8. Next, the servo motor 10 rotates the rotor 2 at high speed according to preset acceleration, deceleration, and rotation speed, and the sample in the rotor 2 is centrifuged.

At the time of unloading, the rotating shaft 8 is centered by the shaft support mechanism 5, the height of the rotor 2 is fixed, and the rotor 2 is rotationally moved by the servo motor 10, and the sample is unloaded from the rotor 2 by the transport means 4. .
Similarly to the sample loading described above, this sample unloading is performed by positioning and unloading the rotor 2 four times to complete the sample unloading from the four buckets.

Japanese Patent Laid-Open No. 11-262682

In the conventional automatic centrifugal device 1, the damper 7 may be deformed by the rotational torque of the servo motor 10 during acceleration and deceleration, and the entire drive unit 3 may rotate. Further, the damper 7 is composed of a spring and rubber, in the case that attenuates the vibration by a frictional force therebetween, the damper 7 is large rather to deformation, it may not be returned to its original position.

Therefore, if the damper 7 is no longer return to deformation to its original position in the rotational direction of the rotor 2, the rotational position detecting mechanism incorporated in the servo motor 10 also causes to move in the rotational direction together, carrying the sample- There was a drawback that the rotor 2 shifted in the rotational direction during unloading. The position of the return after deformation of the damper 7 varies according to the setting of the acceleration and deceleration of the rotor 2, also has a drawback that vary approximately 1 ° stop position of the rotor 2 accordingly.

The deviation in the rotational direction occurs, there is a case where the sample during loading of the sample will attach rotor 2 Tsu nib, a defect that can not be carried into the sample occurs. In addition, in some cases cause a serious accident resulting in damage to the sample at the time of wearing the rotor 2 Tsu nib.

  At the time of carrying out, the conveyance means 4 cannot hold the sample sufficiently, and the sample may be dropped while the conveyance means 4 is moving, which may cause a problem that the conveyance cannot be carried out. Moreover, it may cause a serious accident in which the sample is damaged by dropping.

To overcome the above drawbacks, a method of suppressing the firmer damper 7 modifications can be, when operating centrifuged at high speed in this way, the damper 7 is not completely absorb the rotational vibration, which support the rotating shaft 8 The load of the ball bearings 9a and 9b becomes large, and there arises a problem that the life of these ball bearings 9a and 9b is reduced. Moreover, there because vibration isolation is insufficient, because they may cause abnormal vibration during centrifugation Then rotating at high speed, a problem that must be set lower maximum permissible speed.

  The present invention has been made in view of the above problems, and an object of the process is to provide an automatic centrifuge capable of accurately carrying in and out a sample.

In order to achieve the above object, a first aspect of the present invention is directed to a rotor that houses a sample, a drive unit having a motor that rotationally drives the rotor, a damper that elastically supports the drive unit, and a rotating shaft of the drive unit. have a movable portion that is disposed upwardly moved in the vertical direction, the automatic centrifugal device and a rotation shaft holding mechanism for the rotor to a predetermined height by pushing down the rotating shaft upper end lowers the movable part, the driving part A mechanical positioning mechanism in the rotation direction of the rotation shaft is provided, the position of the rotation shaft in the rotation direction is determined by the positioning mechanism, and the rotation shaft is pushed down by the rotation shaft holding mechanism .

A second aspect of the invention is characterized in that, in the first aspect of the invention, the positioning mechanism is constituted by a quadrangular uneven portion provided on an upper portion of the rotating shaft and a lower portion of the movable portion .

A third aspect of the invention is characterized in that, in the first aspect of the invention, the positioning mechanism is constituted by a plurality of magnets provided at the upper part of the rotating shaft and a single magnet provided at the lower part of the movable part. To do.

According to a fourth aspect of the present invention, in the first aspect of the invention, the positioning mechanism is provided at a plurality of concave portions and a lower portion of the movable portion provided along the circumferential direction at the upper portion of the rotating shaft, and is associated with the concave portion of the rotating shaft. It is characterized by comprising a ball that can be mated and a spring that pushes the ball toward the rotating shaft .

According to the present invention, it is possible to perform the loading and unloading operation of the sample accurately, it is possible to provide an automatic centrifugal device for safe centrifuged and high-speed and long life.

  Embodiments of the present invention will be described below with reference to the accompanying drawings.

  FIG. 1 is a sectional view of an automatic centrifuge 1 according to the present invention. The automatic centrifuge 1 includes a frame 6, a rotor chamber 13, a rotor 2, a drive unit 3, a transport unit 4, a rotary shaft holding mechanism 19, and the like, and is controlled by a control operation unit (not shown). Although not shown in detail, the automatic centrifuge 1 is connected to other devices so as to be controllable through a communication line. Here, the conveying means 4 may be provided in another device (not shown).

The driving unit 3 is supported via a plurality of dampers 7 fixed to the frame 6, and a rotating shaft 8 is rotatably supported by two ball bearings 9a and 9b at the center thereof. An output shaft of a servo motor 10 is connected to the lower end of the rotating shaft 8 by a coupling 11 so that the upper rotor 2 is driven to rotate via the rotating shaft 8. Incidentally, the rotary shaft 8 is provided with a square columnar convex portion 8a and the tip of the protruding portion 8a tapering is provided.

  2 to 4 show the configuration of the rotary shaft holding mechanism 19.

Rotary shaft holding mechanism 19 is always fixed to the rotation center position of the rotor 2 of the top surface of the rotor chamber 13, the spline shaft 14 vertically movable is provided in its lower portion, the lower end of the spline shaft 14 The head 12 is fixed. Then, the bottom surface of the head 12 has recess 12a is provided in the square, at the entrance of the recess 12a tapers are provided. Here, has a concave portion 12a of the head 12 the convex portion 8a of the tip of the square of the rotational shaft 8 is shaped to fit each other, Hamagoji becomes close contact. The concave portion 12a and the convex portion 8a constitute a mechanical positioning mechanism of the present invention, and the rotary shaft 8 is positioned in the rotational direction by fitting them. That is, when the convex portion 8a at the tip of the rotary shaft 8 is fitted into the concave portion 12a of the head 12, the bucket of the rotor 2 is positioned at the loading / unloading position by the conveying means 4, and the rotor 2 is further rotated by 90 °. Each time the remaining bucket is located at the carry-in / carry-out position. The spline shaft 14 is guided by a ball spline outer cylinder 15 and can move up and down without rotating itself.

The spline shaft 14 is always pushed upward by a spring 16a via a washer 17. On the spline shaft 14 is a solenoid 18 is provided, press spline shaft 14 the plunger of the solenoid 18 projects downwardly in a mobile state during loading and unloading, the plunger of the solenoid 18 is in a state before the movement is a spring 16 Is pushed upward together with the spline shaft 14. In order to improve reliability, it is also possible to use a solenoid 18 whose plunger moves in two stages (for example, a 3-position solenoid manufactured by Shindengen Electric Co., Ltd.).

  FIG. 2 shows a state before movement, FIG. 3 shows a first stage movement state, and FIG. 4 shows a second stage movement state. Here, the rotary shaft holding mechanism 19 may shift from the pre-movement state to the second stage movement state without stopping in the first stage movement state.

  Next, a specific operation example of the automatic centrifuge 1 according to the present invention will be described.

At the time of loading / unloading of the sample, the rotor 2 is first rotated and stopped at the loading / unloading position by the transfer means 4, but the servo motor 10 is not braked until it stops, and the rotor 2 can be rotated by external force. It is in a state. This protrusion 8a concave portion 12a is for positioning the rotational direction of the or rotor 2 to rotate moving the rotor 2 to the loading and unloading position so as to fit.

Next, the plunger of the solenoid 18 of the rotating shaft holding mechanism 19 moves to the first stage position, the spline shaft 14 moves downward, and the head 12 presses the tip of the rotating shaft 8. At this time, inclination and lateral displacement of the rotary shaft 8, the convex portion 8a of the tip of the rotary shaft 8 is guided by the taper provided in the concave portion 12a of the head 12, the shift of the center position of the rotary shaft 8 is fixed The

Further, the plunger of the solenoid 18 moves to the second stage position, and the deviation in the rotation direction of the rotor 2 is similarly guided by the taper, so that the rotating shaft 8 rotates to the loading / unloading position of the rotor 2. Here, the rotation shaft 8 and the rotation shaft holding mechanism 19 is rectangular recess 12a, are joined by fitting the convex portions 8a, the rotation of the rotor 2 is restrained position in the rotational direction of the rotor 2 is fixed. At this time, the rotor 2 is brought into a loading / unloading position of the rotor 2, that is, one of the buckets by the conveying means 4 by fitting the rectangular convex portion 8 a of the rotating shaft 8 and the rectangular concave portion 12 a of the head 12 of the rotating shaft holding mechanism 19. Will come to be located. At this position, the sample, that is, the rack is carried in / out, and then the rotor 2 is rotated 90 °, and then the concave portion 12a and the convex portion 8a are fitted again to position the rotor 2 in the rotational direction. Carrying out and carrying out this operation four times completes the loading and unloading.

As another embodiment , a method for positioning and restraining the rotation shaft 8 by the magnetic force, that is , the rotation direction of the rotor 2 , will be described with reference to FIG.

The distal outer peripheral portion of the rotary shaft 8 magnet 20b is fixed. The head 12 is provided with a cylindrical hole that fits into the rotary shaft 8, a taper is provided at the entrance of the hole of the head 12, and a magnet 20a is fixed to the inner periphery. Yes.

  At the time of loading / unloading of the sample, the rotor 2 first rotates and stops at the loading / unloading position. During the stop, the rotor 2 can be rotated by an external force. This is for rotating the rotor 2 to the carry-in / carry-out position at the time of fitting.

Next, the head 12 of the rotating shaft holding mechanism 19 moves and presses the tip of the rotating shaft 8. At this time, the inclination and lateral displacement of the rotating shaft 8 are corrected by the tip of the rotating shaft 8 being guided by a taper provided in the hole of the head 12. Further, the magnet 20 b of the rotating shaft 8 is attracted by the magnet 20 a of the head 12, and the rotating shaft 8 rotates and moves to the loading / unloading position of the rotor 2. After the rotation movement between the head 12 and the rotary shaft 8 is coupled by a magnetic force, is these rotational restraint is performed positioning of the rotational direction of the rotor 2, the position of the rotor 2 is fixed. At this time, as in the above-described embodiment, one of the buckets is positioned at the loading / unloading position.

As another embodiment , a method for positioning and restraining the rotating shaft 8, that is, the rotor 2 in the rotating direction by the ball 21 biased by the spring 16 b built in the rotating shaft holding mechanism 19 will be described with reference to FIG. 6.

The head 12 has been pierced 12 b of the cylindrical taper is provided at the entrance of the hole 12 b. Further, the inner peripheral portion of the hole 12 b of the head 12 ball 21 which is biased is housed by a spring 16b. Tip 8 c of the rotary shaft 8 is in the shape of the hole 12 b and the engagement of the head 12, the outer peripheral portion of the rotary shaft 8, a plurality of the balls 21 provided in the head 12 is fitted hole 8b is that provided.

  At the time of loading / unloading of the sample, the rotor 2 first rotates and stops at the loading / unloading position. During the stop, the rotor 2 can be rotated by an external force. This is for rotating the rotor 2 to the carry-in / carry-out position at the time of fitting.

Next, the head 12 of the rotary shaft holding mechanism 19 moves and presses the tip 8 a of the rotary shaft 8. At this time, inclination and lateral displacement of the rotary shaft 8, the distal end portion 8 c of the rotary shaft 8 is corrected by being guided by the taper provided on the head 12. Further, the rotary shaft 8 is guided by the taper of the hole 8 b provided in the rotary shaft 8 and rotates to the loading / unloading position of the rotor 2. After the rotational movement, the rotating shaft 8 is coupled by fitting the ball 21 provided on the head 12 into the hole 8b formed in the rotating shaft 8, and the rotating shaft 8 is constrained so that the position of the rotor 2 in the rotational direction. A decision is made and the position of the rotor 2 is fixed. At this time, as in the above-described embodiment, one of the buckets is positioned at the loading / unloading position.

It is sectional drawing of the automatic centrifuge which concerns on this invention. It is an expanded sectional view of the rotating shaft holding | maintenance mechanism of the state before the movement of the automatic centrifuge which concerns on this invention. It is an expanded sectional view of the rotating shaft holding | maintenance mechanism of the 1st stage movement state in the automatic centrifuge which concerns on this invention. It is an expanded sectional view of the rotating shaft holding | maintenance mechanism of the 2nd stage movement state in the automatic centrifuge which concerns on this invention. It is an expanded sectional view of the rotating shaft holding mechanism which shows the restricted state of the rotating shaft by the magnetic force which shows other embodiment of this invention. It is an expanded sectional view of the rotating shaft holding mechanism which shows the restricted state of the rotating shaft by the ball urged | biased by the spring built in the rotating shaft holding mechanism which shows other embodiment of this invention. It is sectional drawing which shows an example of the conventional centrifuge.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Automatic centrifuge 2 Rotor 3 Drive part 4 Conveying means 5 Shaft support mechanism 6 Frame 7 Damper 8 Rotating shaft 9a, 9b Ball bearing 10 Servo motor 11 Coupling 12 Head 13 Rotor chamber 14 Spline shaft 15 Ball spline outer cylinder 16a Spring 17 Washer 18 Solenoid 19 Rotating shaft holding mechanism 20a, 20b Magnet 21 Ball

Claims (4)

Possess a driving unit having a motor for rotating the rotor and the rotor housing a sample, and a damper for elastically supporting the drive unit, the movable portion moves in the vertical direction is disposed to the rotary shaft above the drive unit in automatic centrifugal device and a rotation shaft holding mechanism for the rotor to a predetermined height by pushing down the rotating shaft upper end to lower the movable section,
A mechanical positioning mechanism for the rotation direction of the rotation shaft of the drive unit is provided, the position of the rotation shaft in the rotation direction is determined by the positioning mechanism, and the rotation shaft is pushed down by the rotation shaft holding mechanism. Automatic centrifuge to do. 2. The automatic centrifuge according to claim 1 , wherein the positioning mechanism is constituted by a quadrangular convex portion and a concave portion provided at the upper part of the rotating shaft and the lower part of the movable part . 2. The automatic centrifuge according to claim 1 , wherein the positioning mechanism is constituted by a plurality of magnets provided at the upper part of the rotating shaft and one magnet provided at the lower part of the movable part . The positioning mechanism includes a plurality of recesses provided along the circumferential direction at the upper part of the rotation shaft and a lower part of the movable part, and a ball that can be engaged with the recess of the rotation shaft and a spring that pushes the ball toward the rotation shaft. automatic centrifugal device according to claim 1, characterized in that the.

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